This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Percentile Analysis for Differential Gene Expression (PADGE) is a novel tool for identifying genes differentially expressed between two groups of heterogeneous samples. PADGE was designed to compare expression profiles of sample subgroups at a series of percentile cutoffs and to examine the trend of relative expression between sample classes as expression level increases. For comparative analysis, all sample statistical analysis (t test or Wilcoxon rank sum test), the COPA approach (Tomlins et al, Science, 2005) and Kurtosis (Teschendorff, et al, Bioinformatics, 2006) are also implemented and their results are displayed side by side with PADGE, providing a resource of web-based tools for analysis of heterogeneous expression patterns